The present invention relates to a stereoscopic television broadcasting system which includes a stereoscopic video and a stereoscopic television receiver for displaying a stereoscopic picture thereon according to the broadcasting system thereof, and more particularly to a stereoscopic television broadcasting system and a stereoscopic television receiver which are compatible with the existing television receiver.
The fundamental concept of the stereoscopic video system is that the left and right eyes of a viewer observe an object at a slightly different angle of vision. Accordingly, when taking a picture of an object which is intended to be shown to a viewer in a video system, two cameras are located at left and right visual angles for taking a picture.
At this time, assuming that a pictorial image to be seen on the left is a left video and a pictural image to be seen on the right is a right image, at a point of view for indicating stereoscopic video on a screen, the left eye must see only the left video and the right eye must see only the right video.
For this purpose, in the existing picture theaters a stereoscopic movie has been put on the screen by the method as illustrated in FIG. 1. That is to say, the left video of a left projector 1 and the right video of the right projector 2 are projected on a screen 5 through the first and second polarizers 3 and 4, respectively. At this moment, a viewer can see the stereoscopic movie by the video on the screen 5 through a left eye polarizer 6 and a right eye polarizer 7. Both of the polarized 6 and 7 have the same directions of the polarization of light as the first and second polarizers 3 and 4.
In the above system, because the polarization direction of the right eye polarizer 7 is different than the direction of the first polarizer 3 by an angle of 90.degree. it is not possible to see the left video. Similarly, the left eye polarizer 6 has the polarization direction which is different than the direction of the second polarizer 4 by an angle of 90.degree., and thereby it is not possible to see the right video.
Accordingly, a viewer who puts on the left eye and right eye polarizers 6 and 7 can feel the video displayed on the screen 5 stereoscopically.
Another known stereoscopic video system, illustrated in FIG. 2, provides a video which can be seen stereoscopically by a viewer by reproducing a magnetic tape in which a stereoscopic video is recorded with a video cassette tape recorder to display the stereoscopic video on a screen of a television receiver.
In this system, a video tape in which a left video and a right video are recorded in turn, is reproduced by a video cassette tape recorder 11 and the stereoscopic video reproduced by the video cassette tape recorder 11 is applied to a Braun tube 12 of a television receiver. When the left video is displayed on the Braun tube 12, a left eye LCD (liquid crystal display) shutter 13 is opened and a right eye LCD shutter 14 is placed in a closed state so that the left eye can only see the left video. While the right video is displayed on the Braun tube 12, the left eye LCD shutter 13 is placed in a closed state and the right eye LCD shutter 14 is placed in an open state so that the right eye can only see the right video.
However, in the above-mentioned conventional system, as the left or right video is developed on the television receiver, a separate auxiliary circuit for controlling the spectacles of the left eye shutter or the right eye shutter is required. Because the spectacles for the shutters are connected to the television receiver, the number of the televiewers is limited. Furthermore, since the left video and the right video on the television receiver vary in turn, flickering is produced and one side of the LCD shutters is placed in a closed state in turn so that the whole brightness of the screen seems to be dark.